The present invention is in the field of prison security equipment and is more specifically directed to a unique door locking system operable either from a remote location or at the door site.
Medium security penal institutions frequently house inmates in dormitory-like cells or rooms positioned along a common hall or corridor. It is desirable that the inmates be controlled with respect to leaving their room. It is also desirable in some instances to provide permissive locking of the room by the inmate upon his departure while retaining overall central control of the locking function of the door from a secure guard station. It is also desirable to permit the unlocking of the inmate's door by mechanical means from the guard station and at the door site in the event of electrical failure such as might well occur during a fire.
While previously known systems have attempted to provide one or more of the foregoing desirable features, they have failed to achieve widespread acceptance due to a number of shortcomings such as technical complexity, functional inadequacy, and high cost. For example, lightweight electric solenoid bolt control devices have been previously proposed such as in U.S. Pat. No. 3,893,723 which discloses a bolt positioned by a slide member 10 extending between upper and lower solenoids. While the device of this patent might well be satisfactory for low-security installations, it would be easily damaged by any substantial force applied against the bolt when the bolt is in its extended position due to the fact that such force would be immediately conveyed to the actuating solenoids so as to create a bending force on such solenoids to easily destroy the device. The well-known propensity for vandalism in penal institutions would therefore render the device of this patent totally unsatisfactory for penal institution use.
Other specially designed penal door locking systems are not usable with conventional steel door jambs and door assemblies so that the cost of the use of such devices is quite high.
Other prior-known devices such as that shown in U.S. Pat. No. 1,946,384 have employed solenoid actuated bolt members actuated by a pin and slot camming arrangement of complex construction suitable only for light duty in window sashes or the like.
Therefore, it is a primary object of the present invention to provide a new and improved door locking system for penal or similar institutions.
A further object of the present invention is the provision of a new and improved door locking system usable with a conventional steel door jamb.
Yet another object of the present invention is the provision of a new and improved door locking system that can be modularly installed in a conventional steel door jamb and which is operable for locking and unlocking both from a central control station and at the door site.